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MOTOZA 5~100PCS 30x10x2 mm N35 Super Strong Block Neodymium Magnets Rare Earth Magnet 30mm x 10mm x 2 mm Sheet Magnet 30 * 10 * 2 mm (Color : 100pcs): Amazon.com: Industrial & Scientific
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Ferrite Whiteboard Button Magnet 30mm x 6mm - Red – AMF Magnets USA